Tendinopathy and rupture of the tendon of the long head of the biceps brachii muscle: evaluation with MR arthrography.

OBJECTIVE

The purpose of this study was to assess the diagnostic role of MR arthrography in patients with tendinopathy or rupture of the long biceps tendon.

MATERIALS AND METHODS

MR arthrograms of 42 consecutive patients with arthroscopic or surgical confirmation of diagnosis (16 normal biceps tendons, 19 with tendinopathy, and seven with ruptures) were analyzed independently by two radiologists. Visibility of the biceps tendon, caliber changes, contour irregularities, and signal intensities were assessed separately in the parasagittal and axial planes. In addition, the two radiologists made an overall evaluation of abnormalities of the biceps tendon using both MR imaging planes.

RESULTS

The most reliable MR findings for tendinopathy were caliber changes (sensitivity was 59% for observer 1 and 82% for observer 2; specificity was 88% and 64%, respectively) and signal abnormalities (sensitivity, 77% and 88%, respectively; specificity, 75% and 43%, respectively) in the parasagittal plane. Absence of visualization of the tendon in the parasagittal plane was a reliable sign for rupture (sensitivity, 86% and 86%, respectively; specificity, 94% and 87%, respectively). The overall sensitivity for detecting abnormalities (tendinopathy or rupture) was 92% for observer 1 and 89% for observer 2. Specificity was 56% and 81%, respectively.

CONCLUSION

MR findings of tendinopathy and rupture of the biceps tendon are subtle. However, the combination of several MR criteria in two imaging planes makes a reasonably accurate diagnosis possible. The biceps tendon should not only be assessed in the bicipital sulcus on axial images but also on parasagittal images.